Zhang Yun

Zhang Yun (162-208) was a Chinese admiral in the service of Liu Biao (his maternal uncle) and Cao Cao during the Three Kingdoms era.

Biography
Zhang Yun was born in 162 AD, the maternal nephew of Liu Biao. He was highly skilled in naval warfare, and he and Cai Mao commanded Jing Province's navy. In 208, he and Cai Mao went against Liu Biao's dying wishes by appointing his son Liu Cong as the new Governor of Jing Province. Later that year, they advised Liu Cong to surrender to Cao Cao, who was preparing to invade Jing with a massive army, and Cao Cao made Cai Mao and Zhang Yun admirals of his armada. That winter, they both held naval commands at the Battle of Chibi, and they advised Cao Cao to chain his ships together to prevent his soldiers from becoming seasick. Zhou Yu decided to sabotage Cao Cao's war efforts by writing letters to Cai Mao and Zhang Yun under the pretense that they had agreed to betray Cao Cao, only to allow for the letters to fall into Jiang Gan's hands. In response, Jiang Gan reported their treachery to Cao Cao, who had Cai Mao and Zhang Yun executed.